The initial success or otherwise of executive agencies was examined in the Sir Angus Fraser's Fraser Report of 1991. Its main goal was to identify what good practices had emerged from the new model and spread them to other agencies and departments. The report also recommended further powers be devolved from ministers to chief executives.

A whole series of reports and white papers examining governmental delivery were published throughout the 1990s, under both Conservative and Labour governments. During these the agency model became the standard model for delivering public services in the United Kingdom. By 1997 76% of civil servants were employed by an agency. The new Labour government in its first such report – the 1998 Next Steps Report endorsed the model introduced by its predecessor. The most recent review (in 2002, linked below) made two central conclusions (their emphasis):

"The agency model has been a success. Since 1988 agencies have transformed the landscape of government and the responsive and effectiveness of services delivered by Government."

"Some agencies have, however, become disconnected from their departments ... The gulf between policy and delivery is considered by most to have widened."

The latter point is usually made more forcefully by Government critics, describing agencies as "unaccountable quangos".